The work proposed for the coming year involves the synthesis and characterization of a number of novel chelating agents and their testing, as antidotes for mercury poisoning, in animals. The goal of the synthetic program is the development of water soluble dithiocarbamates and vicinal dimercaptols of low molecular weight and minimal toxicity (e.g., such as NaSO3CH2Ch(SH)CH(SH) CH2SO3Na). The animal testing will be carried out so that the relative efficacy of these compounds will be compared directly with compounds currently in use for this purpose (D-penicillamine, N-Acetyl-D,L-penicillamine, 2,3-dimercaptosuccinic acid, and sodium 2,3-dimercaptopropanesulfonate). The animal tests will be carried out on mice receiving mercury in more than one chemical form and by more than one mode of administration. We will also complete the evaluation, in animals, of previously synthesized chelating agents. In addition, a continuing effort will be made to utilize the "mixed ligand chelate" procedure of Schubert in the formulation of optimum dosage procedures for such chelating agents.